White plumes of acid and extremely fine shards of glass billowed into the sky over Hawaii as molten rock from Kilauea volcano poured into the ocean, creating yet another hazard from an eruption that began more than two weeks ago.

Authorities handed out around 2,000 masks for protection as people living near Hawaii’s Kilauea volcano braced for pulverized rock, glass and crystal to rain down after an explosive eruption at the peak’s summit.

A Hawaii volcano is threatening to blow its top in coming days or weeks after sputtering lava for a week, forcing about 2,000 people to evacuate, destroying two dozen homes and threatening a geothermal plant.